[XPERIA X10 Q&A, Help & Troubleshooting] lazy7811:
Hi, Dear friend, Thanks a million for your suggestions. My handset is originally the SO-01B (docomo). I　have runned step1 from original root package with docomo firmware you suggested at the very beginning. However, I failed. I am supprised it only took 3 minutes to complete the flashing for the first step which normally take 5 minutes regarding the others comments. Although the cmd windows shows it completes with ~test in the end without any error, I am afraid it actually missd flashing some files. As for the second suggestion on SEUS method, I will take a trial and report here later. As for the third suggestion on Omnious, I thout I have made a mistake with the oder placing the two files. I have just re-flashed my X10 by Omnious tools according to your suggestion, which the application is with X10i_GENERIC_1234_8465R8A_R1FB001.zip (large file, ~100MB) and Customization is with phone.zip (small file, ~15MB), however I still got a failed results during the application file flashing.(the customization file flashing has not even started ). You may take a look at following log infomation.

Action journal
02:46:27 Flash
02:46:27 Allows to change languages supported by the phone and upgrade its firmware.
02:46:27 Operating system: Microsoft Windows XP Professional Service Pack 3 (build 2600)
02:46:27 Application version: 0.07.2279 (beta)
02:46:27 . The action name is 'Flash'
02:46:27 Selected phone type: Xperia™ X10
02:46:27 i Instructions
02:46:27 i 1. Make sure the phone battery is charged to at least 50%.
02:46:27 i 2. Switch off the phone!
02:46:27 i 3. Remove the phone battery and wait at least 5 seconds before reinserting it!
02:46:27 i 4. Press and hold the return back button, then connect the cable to the phone!
02:46:27 . The action started waiting for the user
02:47:10 . The action finished waiting for the user
02:47:10 Connecting via SEMC USB Flash Device (USB4)...
02:47:10 Device driver version: 2.2.0.5
02:47:10 Detected chipset: QSD8250
02:47:10 Boot mode: EROM
02:47:10 IMEI: 35949603234@@@
02:47:10 Sending loader...
02:47:15 Establishing connection to the server...
02:47:19 Receiving news...
02:47:22 i No news
02:47:22 Actual credit: 0.00
02:47:30 Writing file X10i_GENERIC_1234_8465R8A_R1FB001.zip...
02:50:33 e Failed!
02:50:33 . The action entered shutdown phase
02:50:33 . The action reported failure

Error code
# E39CDD9F86C3082E

Error details
---
4B B3 B7 81 D4 A0 1C 73 C2 C5 F8 25 C2 05 14 45
22 C8 3E 2E F6 CF F4 37 F9 CC B3 85 FC 8A 04 EB
6A 93 97 D6 31 F3 FC 13 5E A7 6D 6B B0 C8 5F 7E
8C 06 02 D8 7E 88 D1 41 5F E4 82 A6 DC 1B 27 CE
18 DF 1F FC F6 E0 77 1E 43 57 F5 22 4F 46 86 82
19 E0 9C 4E E5 DC EE C6 4B 17 FA 16 C1 8D 85 81
9F 90 1D 7D 92 00 EF 1B 3D 43 DD AB 00 6C F1 29
C8 5C B4 F6 D8 AE E1 14 6D D8 5A EF DB E9 3D A7
D6 57 61 8B 9B 3F EA 68 CC DC 1E CE 21 D6 E0 72
E9 F3 30 29 17 26 E0 26 2A A7 53 09 80 06 84 95
16 99 51 A9 25 02 D2 AC DE 55 58 B7 9E 15 74 77
5A E2 15 9C F8 4E 94 E3 6E D1 65 9A 2C 09 32 EA
CA 0D 40 CB 42 6E AE 64 50 14 C8 E7 7E 83 F8 E2
44 FD FE 4E 36 F1 B4 73 8E C5 D8 C9 12 59 BC AB
F8 FE 60 DF A6 31 C4 2C 1E 6B E8 79 56 30 9A A9
E6 7D 70 DF EA 91 D4 D9 9A CE 65 04
---

Flashing with DoCOMO SO-R1EA025-DEK, Failed too.

Action journal
03:11:20 Flash
03:11:20 Allows to change languages supported by the phone and upgrade its firmware.
03:11:20 Operating system: Microsoft Windows XP Professional Service Pack 3 (build 2600)
03:11:20 Application version: 0.07.2279 (beta)
03:11:20 . The action name is 'Flash'
03:11:20 Selected phone type: Xperia™ X10
03:11:20 i Instructions
03:11:20 i 1. Make sure the phone battery is charged to at least 50%.
03:11:20 i 2. Switch off the phone!
03:11:20 i 3. Remove the phone battery and wait at least 5 seconds before reinserting it!
03:11:20 i 4. Press and hold the return back button, then connect the cable to the phone!
03:11:20 . The action started waiting for the user
03:11:35 . The action finished waiting for the user
03:11:35 Connecting via SEMC USB Flash Device (USB4)...
03:11:35 Device driver version: 2.2.0.5
03:11:35 Detected chipset: QSD8250
03:11:35 Boot mode: EROM
03:11:35 IMEI: 35949603234@@@
03:11:35 Sending loader...
03:11:40 Establishing connection to the server...
03:11:43 Receiving news...
03:11:45 i No news
03:11:46 Actual credit: 0.00
03:11:54 Writing file FILE_277398338_1275040924000_1274947104000_277398125_112659344_INFILE_LONGTERM.zip...
03:14:56 e Failed!
03:14:56 . The action entered shutdown phase
03:14:56 . The action reported failure

Error code
# E39CDD9F86C3082E

Error details
---
6F CF 37 25 E8 9C D0 F1 4A 7F 34 00 0E B5 A8 80
E4 4C 92 CA 2A 2D E0 AB ED 76 EF 5F 30 F8 98 07
22 29 7B B2 CD F1 10 AF 96 63 E9 0F 7C 44 DB 12
18 C2 F6 82 A2 6A 3D 23 4B 5E D6 42 10 69 B3 1C
EC 1B CB 58 36 22 A3 E2 4B 6D 39 F8 03 CA 3A AE
71 5A C8 D4 45 3E C2 A4 5F 2D 2E CC 8D 01 E9 ED
2B 54 B1 99 EE 7C 63 59 F5 07 D1 B1 4C E0 0D 3B
A0 E6 D8 AC 84 B2 0D 88 85 E2 7E 75 97 65 A9 75
5E 13 35 D1 5B 03 26 EA 44 66 2A EA ED 5A AC A0
7D C9 9C 33 CB 3A 0C 44 3E E3 07 2D B0 74 E8 79
5E DD 45 33 D9 FE 3E 10 16 91 2C D3 AE 66 08 27
32 3F AB 7B 24 52 80 81 86 6B C1 7E 1C 85 A6 C6
C2 37 14 6F 7E 52 62 98 58 2E F4 C3 32 0F 4C CE
2C 47 52 2A 6A 13 A0 EF 66 FF 04 ED 5E D5 28 C7
4C C4 F4 3B 26 B3 B0 90 D6 2F EC 63 E6 42 66 45
72 C7 E4 7B B6 73 C0 BB 8E F4 B1 60
---

I will report more results later since it is already 4 am in Japan. I have to go to bed.

Thank you again for your big help.